Earth working and construction type machines, for example motor graders, wheel loaders, excavators, agricultural tractors, dozers, etc. include a cab from which an operator controls the machine and attached implements. The cab protects the operator from any adverse environment and also protects the operator from injury in case of machine roll over. For efficient and effective operation of the machine, an operator should have unobstructed view of the machine and its surrounding objects and environment, including front, sides and back of the machine. An operator of the machine may need to have an unobstructed rear view of the machine while situated in the operator seat inside the cab. For example, the operator may need to have a view on the backside for moving the machine backwards or for monitoring proper functioning of any part of the machine or any implement mounted on the back portion of the machine.
A cab generally includes a floor, a roof and upright support members that extend between the floor and the roof. The upright support members support the roof of the cab above the floor. The upright support members may be used for mounting various components, for example, an air handling duct or other wirings or conduits. Further, such support members along with other parts of the cab are designed structurally strong to act as a roll over protection system (ROPS). As a result, the bigger dimension of such support members may be detrimental in providing an unobstructed rear view from the operator seat. U.S. Pat. No. 3,279,843 discloses a cab with a pair of diagonal members, a pair of cross-members and a pair of vertical braces forming rear support members for the cab. Such multiple members and braces as a rear support members may fail to provide an unobstructed rear view of the machine from the operator seat inside the cab.